Onwards and upwards, Blimy, good to hear you are sticking at it.
As Blimy has shown, you need to be getting an aptitude score of 130, and an AIB pass. Aircrew selection for BRNC is based on aptitude, given that you also passed AIB. A high pass at AIB won't make up for a low aptitude score, even if it is a pass (112 pass score).
I'm told that the following is current:
pass 112 up to 180 max while anything over 150 is good